Communications services have historically been provided over wireline networks such as the Public Switched Telephone Network (PSTN). Currently, communications services are also provided over a wide variety of wireless networks such as cellular networks and WLANs. Common cellular network formats include Global System for Mobile Communication (GSM) networks and Interim Standard 41 (IS41) networks. WLANs utilize technologies, such as IEEE™ standards 802.11, 802.11a, 802.11b, and 802.11g, Wireless-Fidelity (Wi-Fi) supported by the Wireless Ethernet Compatibility Alliance, BLUETOOTH™ supported by Bluetooth SIG, Inc., Home Radio Frequency (HomeRF) supported by HomeRF Working Group Inc., High Performance Radio Local Area Network (HiperLAN) developed by the European Telecommunications Standards Institute, and the like.
A wireless communication device, such as a mobile telephone, typically communicates in a cellular network by detecting some form of beacon signal transmitted by one of a plurality of Base Transceiver Stations (BTSs) and then synchronizing itself to that BTS. BTSs include radio transceivers that define a geographic region, known as a cell or wireless service area, and coordinates radio link protocols with wireless communication devices. The BTSs are the networking components of a cellular network from which all signals are sent and received. All BTSs in a cellular network are connected to a Mobile Switching Center (MSC) by landline or microwave links. The MSC controls the switching between the Public Switched Telephone Network (PSTN) and the cell site for all wireline-to-mobile and mobile-to-wireline calls. The MSC also processes mobile unit status data received from the cell-site controllers, switches calls to other cells, processes diagnostic information, and compiles billing statistics.
Roaming refers to the ability of a wireless communication device to move from the coverage of one wireless service area to another wireless service area without interruption in service or loss of connectivity. The North American Cellular Network (NACN) is an organization of cellular providers that facilitates cellular calls across the United States to be linked for seamless roaming. The components of the NACN include switches, Home Location Registers (HLRs), Authentication Centers (AuCs), Equipment Identify Registers (EIRs), Visitor Location Registers (VLRs), service control points, and other intelligent peripherals. An HLR is a database for storing a subscriber's feature profile, such as the Mobile Identification Number (MIN), Electronic Serial Number (ESN) of the wireless communication device, and the features of the customer (such as call forwarding, call waiting, 3-way calling, voice mail, etc.). In a GSM cellular network, the AuC includes functionality that is responsible for authenticating information provided by the subscriber identification module (SIM) card of each wireless communication device that attempts to connect to the GSM core network (typically when the phone is powered on). Once the authentication is successful, the HLR is allowed to manage the wireless communication device, SIM, and other services provided by the network. The AuC may be co-located with an HLR. An EIR function may be used to determine whether a wireless communication device has been banned from the network, such as when a wireless communication device is reported as stolen. The EIR function may be co-located with an HLR. A VLR is a network database, which is typically associated with an MSC that serves a particular geographic service area. A VLR temporarily stores information and provides mobility management functions related to those mobile subscribers that are being served by the associated MSC. A VLR is adapted to notify a mobile subscriber's HLR in response to the mobile subscriber entering the VLR's service area. In a GSM network, a MAP UpdateLocation message is used by a VLR to notify a mobile subscriber's HLR that the subscriber has entered into the VLR's service area. The VLR can include information, such as MIN and ESN, about a roaming wireless communication device. A VLR can be a part of the MSC.
WLANs can be used to provide Internet or other network access to mobile communication devices, such as laptops, personal digital assistants (PDAs), and smartphones. WLAN-enabled communication devices can communicate with a WLAN via one or more access points that act as a communication hub for the WLAN-enabled device to communicate with a wired network. A hotspot is a geographic area in which an Access Point (AP) provides public wireless broadband network services to communication devices through the WLAN. Hotspots are commonly located in heavily populated areas such as airports, train stations, libraries, marinas, conventions centers, shopping malls, and hotels. WLAN-enabled devices can roam between hotspots.
WLAN service subscribers can be provided subscription management and authentication, authorization, and accounting (AAA) services by an application service provider (ASP) aggregator. An ASP aggregator is a third party entity that can allow subscribers to access WLAN services at multiple hotspots with a single subscription. Several APs can be connected to an AAA server for providing WLAN services to multiple hotspots. Typically when a WLAN-enabled device attempts to connect to a WLAN, a username and password must be provided to pass to the AAA server. The AAA server can then pass the username and password to an HLR, which checks that the username and password is acceptable and then authorizes access to the WLAN.
An AAA server handles user requests for access to computer resources and, for an enterprise network, provides AAA services. The AAA server typically interacts with network access and gateway servers and with databases and directories containing user information. Remote Authentication Dial-In User Service (RADIUS) is a client/server protocol and software that enables access points to communicates with AAA servers. The AAA server uses GSM Mobile Application Part (MAP) protocols to communicate with HLRs to authenticate WLAN users and authorize their access to requested WLAN service. RADIUS allows an ASP aggregator to maintain user profiles in a central database that all remote servers can share.
Currently, access to cellular networks can be provided at hotspots. This service enables a subscriber to a cellular network to roam into the hotspot coverage area and receive service to the cellular network. The cellular service is provided by linking to the HLR of the cellular network in order to authenticate the subscriber. Each time AAA, mobility management (e.g., roaming), or billing service is required, the cellular network must be accessed, which can place a significant burden on cellular network resources.
Accordingly, there exists a need for improved integration of Wireless Local Area Network (WLAN) and cellular network based systems.